Couric left her long-time role as co-host of NBC's "Today" in 2006 to sit in the anchor chair formerly held by CBS legends Walter Cronkite and Dan Rather. But reviews have been uneven for Couric.

Couric commanded a $15 million salary to take the CBS anchor job but the network remained last month the major network newscasts behind NBC and ABC. In fact, CBS' ratings are believed to be their lowest in two decades, according to mediabistro.com.

The AP says Couric will leave CBS Evening News on June 4 and begin her new show next year. Scott Pelley from "60 Minutes" is considered a leading candidate to replace Couric.